by Charlene Burgi
Some gardeners like to start their vegetable garden from seed, while others prefer buying plants ready to go into the soil to bypass the time and commitment of working with seed germination. Either process will provide an abundant crop to supply your family as well as the neighborhood, so there is no right or wrong choice.
| Seed packets
Personally, I find a special joy when starting a garden from seed because of the miraculous transformation of a hard tiny speck into something completely different. The birth of a plant from seed is amazing.
I was reading a book on plant propagation the other day, and one chapter touched on "conditioning" seeds. Many soils require conditioning, but seeds? This term was new to me and, I might add, the very reason I love gardening—there's always more to learn.
Seed conditioning varies with each type of plant. Most seeds have some type of inhibitor that prevents germination unless the seed is exposed to certain conditions. This is nature’s way of ensuring seeds don’t germinate until environmental conditions are favorable for survival. For example, most seeds purchased in packets are dry conditioned—that is, these seeds must be separated from the parent plant and dried. This type of conditioning is typical in annuals; once the seeds have dried, the natural inhibitor diminishes. Then when the seed is exposed to moisture, the process of germination occurs.
Some seeds such as sweet peas and morning glories have a very hard seed coat that prevents moisture from penetrating without the aid of the gardener taking the extra step of filing or nicking the seed—a process known as scarification. An easier method is to soak the seeds in warm water overnight to soften the hard tissue casing. Heat can also cause scarification: Some pines, for example, depend on fire to release the seeds in their cones to repopulate a forest.
Some seeds need just the opposite exposure—they require cold temperatures followed by warmer temperatures for germination. This system is known as stratification. Cold temperatures cause the growth inhibitors to delay germination until the weather warms. This prevents seeds from germinating during the winter when tiny seedlings could be lost to frost.
The bottom line: Know your seeds and if any special conditioning is required for germination. In addition, remember that different plants have different germination periods. For maximum performance, note the recommended number of days between planting and the last frost date in Marin, and track your findings on a calendar. The joy comes when you see little seedlings poking their heads out of the planting medium.